It's actually impossible to prove or disprove, as the evidence can only ever be anecdotal; it can't be tested in a lab. Nobody can demonstrate that they wouldn't have got the girl had they not used a specific tactic or vice versa.
It can't be denied though, if you make a lot of approaches and hit on more and more women, you are going to get more success, purely by playing the numbers game. A lot of it may account for this, plus the fact that you become increasingly desensitized to rejection and used to talking to women.
It also stands to reason, if you have absolutely no idea what to say to women, it could be handy to learn a few gimmicks until you can think of your own stuff. If you get too dependent on this though, it could fuck you up in the long run.
It actually reminds me of teaching a bit. I have to have material prepared for my classes and, when I've prepared well, the classes flow very nicely. If you are a new teacher and you do not prepare, your class will be a fucking disaster! Only later, when you are experienced, can you wing it.
However, if you get too attached to the material and it runs out, there can be awkward moments and uncomfortable silences in the class. It can also be weird when you see a student down town, and can't think of anything to say without your lesson plan in front of you.
To make sure that this doesn't happen to me I often freestyle large parts of or even whole lessons sometimes. I hope that's not too weirdly off point, it's just my job reminds of pick up in this way.
As far as the
PUA industry goes.... I don't know man, I'm sure it's exploitative on quite a few levels... but these guys DO seem to do really well with women. Richard Gambler, for one, appears to have the biggest abundance of hot women that I have ever seen in the community.